1. Field of the Invention
Embodiments of the present invention relate to digital processing architectures. More particularly, embodiments of the present invention relate to the design and operation of a programmable scalar node in an adaptive computing engine.
2. Description of the Background Art
Many different types of integrated circuit technology are employed to achieve optimal cost versus performance characteristics in electronic devices. For example, application specific integrated circuits (ASICs) and field programmable gate array (FPGAs) are two types of integrated circuit technology that are widely employed to implement a variety of electronic functions.
ASICs and FPGAs are preferred for many integrated circuit applications because of the ability to reduce the design cycle and quickly produce new or different functions. ASICs may be customized by merely generating masks for one or more metal interconnect layers, which reduces the manufacturing process by several weeks. FPGAs may be customized in the field by programming fusible links to connect logic elements to achieve the desired functions.
While widely used, ASICs and FPGAs suffer from well-known drawbacks and limitations. For example, both technologies generally are slower, require larger die and are less power efficient than dedicated or custom integrated circuits. Notwithstanding the drawbacks and limitations, ASICs and FPGAs are often used in portable or battery-powered digital devices because the product life cycle is usually very short. Thus, it is impracticable to design custom or dedicated integrated circuits.
Many digital devices, such as cellular telephones, personal digital assistants (PDAs), notebook computers and other battery-powered devices, require several low power integrated circuits so the device can perform a variety of functions. For example, there is a need for a cellular telephone that can perform communication functions, high-speed data transmission, location awareness, true handwriting, speech and visual recognition, as well as other functions such as calendaring, word processing, accessing the Internet and responding to electronic mail (e-mail), digital photography. It is also desirable that other functions that have historically been performed by PDAs or notebook computers rather than a cellular telephone be provided in a small portable power efficient package. Clearly, to achieve all of these functions in a small package, there is a great need to minimize the number of integrated circuits required to perform these functions in order to reduce the size and weight of the digital devices and to improve power efficiency.
It is therefore desirable to provide an integrated circuit that can be adapted to perform one of several different functions. There is also a great need for a mobile communication device, such as cellular phone that interface with multiple communication worldwide standards so that users can roam throughout the world while staying “connected” via a single mobile device that also provides the features to call, page, email, and connect to the Internet.